<div dir="ltr">Gavin,<div><br></div><div style>You may also want to poke around in the Appleseed Render source code, as if I recall correctly they have a pretty modern approach to deformation blur, and a very similar architecture to Cycles as a whole.</div>
</div><div class="gmail_extra"><br><br><div class="gmail_quote">On Mon, Jun 10, 2013 at 2:33 PM, Gavin Howard <span dir="ltr"><<a href="mailto:gavin.d.howard@gmail.com" target="_blank">gavin.d.howard@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><p dir="ltr"> Hello all,</p>
<p dir="ltr"> Brecht, thank you. I will get going on that patch. Stuart, if you don't think that's a good idea, let me know. Otherwise, I'll use that to focus my code exploration.</p>
<p dir="ltr"> Nate, because of the nature of deformation motion blur, it will include curved blur. It has to. The reason is because most deformation is done by rotation. My current plan is to simply add multi-step export to the Cycles addon. (All you smart devs should yell at me if that's a bad idea.) I am also going to browse LuxRender's source code to see how they did it. Regardless, at the end of this summer, not only will Cycles have deformation motion blur, it will get multi-step export (steps will be specified by the user) and curved motion blur by side effect.</p>
<p dir="ltr"> God Bless,<br>
Gavin Howard</p><div class="HOEnZb"><div class="h5">
<div class="gmail_quote">On Jun 10, 2013 9:39 AM, "Nate Wiebe" <<a href="mailto:natewiebe13@gmail.com" target="_blank">natewiebe13@gmail.com</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr"><div>Not entirely related, but will the scope of this GSOC cover curved motion blur?<br><br></div>-NateW<br></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Mon, Jun 10, 2013 at 11:29 AM, Brecht Van Lommel <span dir="ltr"><<a href="mailto:brechtvanlommel@pandora.be" target="_blank">brechtvanlommel@pandora.be</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Yes Blender supports this, it does scene.frame_set(frame, 0.0) now,<br>
the second value is a subframe value between 0.0 and 1.0.<br>
<div><div><br>
On Mon, Jun 10, 2013 at 4:58 PM, Gavin Howard <<a href="mailto:gavin.d.howard@gmail.com" target="_blank">gavin.d.howard@gmail.com</a>> wrote:<br>
> Hello,<br>
><br>
> Does Blender allow exporting at arbitrary subframes? If not, that might<br>
> be a problem. If so, then Stuart has me exploring the code, and I think that<br>
> I could write the patch while doing so. Does that sound okay?<br>
><br>
> God Bless,<br>
> Gavin Howard<br>
><br>
> On Jun 9, 2013 6:34 AM, "Brecht Van Lommel" <<a href="mailto:brechtvanlommel@pandora.be" target="_blank">brechtvanlommel@pandora.be</a>><br>
> wrote:<br>
>><br>
>> We should support exporting at the exact shutter time. At the time I<br>
>> implemented motion blur evaluation at subframes was actually broken<br>
>> for shape keys and physics systems so I didn't use it, but that has<br>
>> been fixed since.<br>
>><br>
>> However, exporting motion from the frame positions may be useful to<br>
>> keep as it may give more predictable results in some cases. When<br>
>> you're editing animations that's the only thing you actually see in<br>
>> animation playback, so the motion between those frames may contain<br>
>> some unexpected things that you don't want to render.<br>
>><br>
>> I don't know how common that is, did not look at .blend files yet to<br>
>> see how different the results are, if it is an issue we should<br>
>> probably have an option (off by default) to only export motion from<br>
>> integer frame numbers and no subframes.<br>
>><br>
>> On Sat, Jun 8, 2013 at 7:36 PM, Gavin Howard <<a href="mailto:gavin.d.howard@gmail.com" target="_blank">gavin.d.howard@gmail.com</a>><br>
>> wrote:<br>
>> > Hello all,<br>
>> ><br>
>> > I have a question about implementation. I have been told by<br>
>> > Brecht that currently, the Cycles addon exports three steps for motion<br>
>> > blur to the renderer: one at the previous frame, one at the current<br>
>> > frame, and one at the next frame.<br>
>> ><br>
>> > Now, my memory may not be serving me well here, so I may have<br>
>> > gotten the details wrong. But if not, shouldn't the addon actually use<br>
>> > the shutter time to determine the first and third steps? For example,<br>
>> > shouldn't the addon export a step at the start of the shutter time,<br>
>> > one at the current frame, and one at the end of the shutter time?<br>
>> > Also, I think this type of reasoning should apply even when multi-step<br>
>> > (more than 3) motion blur is added. (Multi-step blur is needed for my<br>
>> > Deformation Motion Blur GSoC project, so I will add it over the<br>
>> > summer.)<br>
>> ><br>
>> > In short, I think that the shutter time should be the goto for<br>
>> > exporting motion blur steps. If it is, then just ignore this. But if<br>
>> > it's not, should we change it? Anyway, that's my two cents.<br>
>> ><br>
>> > God Bless,<br>
>> > Gavin Howard<br>
>> > _______________________________________________<br>
>> > Bf-cycles mailing list<br>
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